Tract-specific analysis for investigation of Alzheimer disease: a brief review.

Magnetic resonance diffusion tensor imaging is a noninvasive technique that can identify white matter tracts by evaluating bulk diffusion of water in three dimensions and can thus describe the microarchitectural characteristics of local brain tissue. Several recent reports have shown that mapping of diffusion parameters is potentially useful for speculating about the pathology of Alzheimer disease (AD). These reports have employed image-analysis approaches, including region-of-interest measurement, voxel-based analysis, tract-based spatial statistics, and tract-specific analysis (TSA). The present review focuses on TSA to investigate AD. An overview of the changes in diffusion properties of AD measured using TSA is presented and discussed.